Replace BMW Key Battery It's probably the time to change your battery if your BMW key won't open your car or turn the engine. Fortunately, it's a simple fix. It's as easy as removing the key fob, then replace the battery and gently place it back. Follow these steps and https://car-key-repairs81453.dailyhitblog.com/35600147/this-is-the-good-and-bad-about-bmw-key-fobs